The anti-graft agency recently announced the money, most of which was received ahead of the March 2013 general elections, came from donations and not from state investment fund 1MDB.

More than that allowed

The People’s Justice Party said the money was 26 times above the amount that Mr. Najib’s ruling National Front coalition was allowed to spend in the elections. The National Front, which has ruled since independence from Britain in 1957, won the elections but lost the popular vote for the first time to an opposition alliance that includes the People’s Justice Party.

The party’s vice-president, Nurul Izzah Anwar, said the lawsuit will reveal “all kinds of bribes and corrupt tactics” allegedly used by the National Front to win the elections. With evidence of corrupt transactions, she said the results of the 2013 general elections should be nullified and new polls should be called.

The party also named 1MDB, the Election Commission and Adnan Mansor, secretary-general of Mr. Najib’s ruling Malay party, in the lawsuit.

Government officials couldn’t be immediately reached for comment.

42 billion ringgit debt

1MDB, set up in 2009 by Mr. Najib who still chairs its advisory board, has debts of 42 billion ringgit ($10.4 billion) after its energy ventures abroad faltered. Critics have voiced concern about 1MDB’s massive debt and lack of transparency.

The 1MDB crisis has partly contributed to the Malaysian currency crashing to 4 ringgit to the dollar on Wednesday, the lowest since the 1997-98 Asian financial crisis.

Meanwhile, Malaysia’s ringgit weakened past the psychologically important 4 per dollar level on Wednesday as regional currencies lost ground after China allowed the yuan to drop for the second straight day.